So.... my very preliminary testing with our new Mac Pro using the plugin I use most (filmconvert -FC) anyway, shows that Premiere CC needs more optimization for the dual GPUs. In fact, I'd say the CPU utilization is not up to snuff either. I know FC only uses one GPU presently from the developer. That will change. In the meantime, using a couple of typical projects with that plugin as an example, I'm only seeing 25-45% speed up in exports over our maxed out late 2012 27" iMac exporting the same project. That's significant of course but not the 100%+ one would think we would be seeing at the least given the MacPro config of 8 cores and dual D700s. Premiere Pro CC seems in fact to never maximize CPU (never mind GPUs). I have yet, in my very limited testing, see it "pin the meters" like I did on the iMac. Of course that's just testing now two short (under 5 min) projects, and it depends on what one is doing. Some stuff is much, much faster like Red Giant's Denoiser II or Warp Stabilizer VFX. The improvement there can be 3-4x faster anecdotally. I used to avoid them for speed reasons unless absolutely needed a lot of the time but now they are fast enough to rely on quickly. Other stuff unrelated top PPro CC like DxO PRIME noise removal on RAW stills is much faster too, as is Photoshop CC. Some effects like blur, sharpening, resize there are nearly instant now even on giga pixel files in Photoshop CC. And of course FCPX is much faster on it but I hate the whole editing paradigm. The timeline is just horrid on it; simple things like replacing a word in someone's dialogue is a multi click, multistep process that is nearly instant in Premiere and most every other NLE. Just to try to see your whole timeline is a chore, to see what your edits and sound are in detail are problematic, trying to keep things in sync is a chore, and you can't even zoom your timeline window to full screen! It's just not for me until the fundamentals of the program change. The amount of time gained by using it for exports would be lost in counteracting some of Apple's "magnetic" timeline issues. I'm sure Adobe will improve over time. They have to to stay competitive. In the meantime I'll take the 45%... but I wish I saw much more improvement given the cost and hardware differential. Unfortunately, for now, the mainstream reviews I have seen regarding PPro performance on this machine were right. More to come as I continue to test.